Analyses of program effectiveness and costs must consider and include (if relevant) several categories of effects: program adherence, direct and indirect program costs, intangible costs, health benefits and harms, direct and indirect economic benefits from the program, and intangible economic benefits. In geriatrics and gerontology, there are a number of methodologic issues and problems specific to the measurement and analysis of these effects. In the assessment of effectiveness and adherence, these issues include: comprehensiveness of the cost estimates, inclusion of "out-of-pocket" health costs, consideration of indirect costs incurred by caregivers, and the valuation of preferences and utilities. To deal with these issues in the context of the proposed intervention studies, we propose a research resource core (RRC) to focus on the measurement of the costs and the effectiveness of the proposed interventions. This core will bring together individuals with expertise in the fields of geriatrics and gerontology, health services research and economics, cost-effectiveness analysis, measurement of health status, and measurement of compliance or adherence. The core will offer 2 levels of services: 1) basic services to include the selection, use, and testing of measurement methods; and 2) cost-effectiveness services to focus on methods for such analyses. Measurement instruments and methods will be chosen and adapted depending on study hypotheses and subject populations. Depending on the intervention, different levels of cost-effectiveness and cost- utility analysis are proposed.